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positive discrimination
positive economics
positive gloss
positive prescription
positive vetting
positive yield curve
positively
positivism
positron
positron emission tomography
positronium
posole
posology
posse
posse cut
possess
possessed
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positron
pos·i·tron [ pózzə tròn ] (plural pos·i·trons)


noun 
Definition:
 
electron antiparticle: an elementary particle of antimatter that has the same mass as an electron, but the opposite electrical charge
[Mid-20th century. Blend of positive + electron]
Encarta® World English Dictionary [North American Edition] © & (P)2007 Microsoft Corporation. All rights reserved. Developed for Microsoft by Bloomsbury Publishing Plc.
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